Shielding tape with multiple foil layers

ABSTRACT

A coaxial cable of the present invention comprises a center conductor, a dielectric surrounding the center conductor, a shielding tape surrounding the dielectric, a braided metal surrounding the shielding tape, and an outer jacket surrounding the braided metal. The shielding tape comprises: (i) a first shielding layer bonded to a first separating layer; (ii) a second shielding layer bonded to the first separating layer and a second separating layer; and (iii) a third shielding layer bonded to the second separating layer. The present invention eliminates the potential problem of the outer shielding structures separating and interfering with connector attachment. Furthermore, the use of three or more shielding layers in the shielding tape of the present invention improves the flex life of the shield tape by covering micro-cracks in the metal layers with additional shielding layers, thus reducing signal egress or ingress. Accordingly, the present invention provides cost savings and/or an improvement in shielding performance.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 12/605,908, filed Oct. 26, 2009, titled “Shielding Tape WithMultiple Foil Layers.” which claims the benefit of and priority to U.S.Provisional Patent Application No. 61/226,250, filed Jul. 16, 2009,titled “Shielding Tape With Multiple Foil Layers,” the disclosures ofwhich are fully incorporated herein by reference for all purposes.

BACKGROUND

Shielding is used in a variety of cables to reduce electricalinterference that could affect a signal travelling through the cable.The shielding also helps to prevent the signal from radiating from thecable and interfering with other devices. One such type of shieldingincludes either one or two layers of aluminum or other shieldingmaterial (such as silver, copper, or Mu-metal) wherein each shieldinglayer is laminated onto (and if there is more than one shielding layer,each shielding layer is separated by) a separating layer, such as aplastic, e.g., polyethylene terephthalate (“PET”) or a polyolefin suchas polypropylene (“PP”). This type of shielding that combines layers ofshielding material and separating layers is often referred to as either“foil,” “laminated tape,” “shielding tape,” “shielding laminate tape,”and combinations or variations thereof.

In some cables, such as coaxial cables, multiple layers of shieldingtape (each of which has either one shielding layer or two shieldinglayers) are employed in the cable. For example, “tri-shield” cableincludes an inner foil surrounded by a braid, which is in turnsurrounded by an outer foil. “Quad-shield” cable includes an inner foilsurrounded by an inner braid, which is in turn surrounded by an outerfoil, in turn surrounded by an outer braid.

Multiple layers of shielding tape, while providing better shieldingperformance, also add to the cost and complexity of producing thecabling. Conventional shielding tape, with only one or two shieldinglayers, is susceptible to allowing RF signal egress or ingress asmicro-cracks form in the shielding layers and align with each other as aresult of flexing the cable. Furthermore, the outer shielding structures(such as tape) of conventional cables must often be removed in order toattach a connector. These outer shielding structures may also separateand interfere with the attachment of a connector to the cable.

The present invention overcomes these and other problems associated withconventional shielding tape and cable designs. In particular, by usingshielding tape of the present invention (that incorporates three or moreshielding layers) as the inner foil of a cable, outer shieldingstructures (such as shielding tape and/or braids) can be eliminated.This not only reduces the cost of the cable, but obviates the need forthese outer shielding structures to be removed to attach a connector tothe cable. Likewise, by including additional shielding layers to theinner shielding tape, the present invention eliminates the potentialproblem of the outer shielding structures separating and interferingwith connector attachment. Furthermore, the use of three or moreshielding layers in the shielding tape of the present invention improvesthe flex life of the shield tape by covering micro-cracks in the metallayers with additional shielding layers, thus reducing signal egress oringress.

SUMMARY OF THE INVENTION

A coaxial cable of the present invention comprises a center conductor, adielectric surrounding the center conductor, a shielding tapesurrounding the dielectric, a braided metal surrounding the shieldingtape, and an outer jacket surrounding the braided metal. The shieldingtape comprises: (i) a first shielding layer bonded to a first separatinglayer; (ii) a second shielding layer bonded to the first separatinglayer and a second separating layer; and (iii) a third shielding layerbonded to the second separating layer. The present invention eliminatesthe potential problem of the outer shielding structures separating andinterfering with connector attachment. Furthermore, the use of three ormore shielding layers in the shielding tape of the present inventionimproves the flex life of the shield tape by covering micro-cracks inthe metal layers with additional shielding layers, thus reducing signalegress or ingress. Accordingly, the present invention provides costsavings and/or an improvement in shielding performance.

A cable according to another aspect of the present invention includes acenter conductor and a shielding tape surrounding the center conductor.The shielding tape comprises (i) a first shielding layer bonded to afirst separating layer; (ii) a second shielding layer bonded to thefirst separating layer and a second separating layer; and (iii) a thirdshielding layer bonded to the second separating layer.

A shielding tape according to another aspect of the present inventioncomprises a first shielding layer bonded to a first separating layer, asecond shielding layer bonded to the first separating layer and a secondseparating layer, and a third shielding layer bonded to the secondseparating layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a preferred embodiment of a shielding tape according to theinvention.

FIG. 2 shows the shielding tape of FIG. 1 included in a coaxial cable.

FIG. 3 shows diagrams illustrating how a shielding tape according to theinvention is manufactured.

FIG. 4 is a graph depicting the improved performance of a preferredembodiment of the invention over a shielding tape having two shieldinglayers.

FIG. 5A shows a side perspective view of a tri-shield coaxial cablehaving an additional layer of shielding tape configured in accordancewith the present technology.

FIG. 5B shows a side perspective view of a quad-shield coaxial cableconfigured in accordance with the present technology.

FIG. 6 shows a cross-sectional end view of a cable having a first centerconductor and a second center conductor surrounded by a shielding tapeconfigured in accordance with the present technology.

FIG. 7 shows a cross-sectional view of shielding tape having fourshielding layers configured in accordance with the present technology.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

Turning now to the drawings, where the purpose is to describe preferredembodiments of the invention and not limit same, FIG. 1 shows ashielding tape 10.

Shielding tape 10 according to the present invention comprises at leastthree layers of shielding material (which are also called “shieldinglayers”). As shown in FIG. 1, the shielding tape 10 comprises a laminatestructure of aluminum 20/PET 30/aluminum 40/PET 50/aluminum 60, with ahot melt adhesive 70 (which is preferably EAA or EMAA) applied toaluminum layer 60.

The aluminum layers of the exemplary shielding tape 10 are each about 9microns thick, while the separating layers are about 12 microns thick.There is also a layer of adhesive between each aluminum/PET layer ofabout 2 microns thick. The adhesive layer 70 is about 25 microns thick.Other embodiments of the present invention may include shielding layersof at least 3 microns thick, separating layers of at least 4 micronsthick, and adhesive layers of at least 8 microns thick. Multipleshielding layers need not all be of the same thickness. Likewise,multiple separating layers and/or adhesive layers need not all have thesame thickness.

The layers of shielding material may comprise any suitable material,such as aluminum, copper, silver, a magnetic alloy (such as Mu-metal),or combinations thereof, and need not each be formed from the samematerial(s). The shielding layers may be any suitable thickness, andneed not each be the same thickness. Additionally, while the exemplaryshielding tape depicted in FIG. 1 comprises three shielding layers,alternate embodiments of the present invention may include any suitablenumber of shielding layers greater than two, such as four or more layersof shielding material, each separated by a separator material. Forexample, FIG. 7 shows a shielding tape 10 comprising a first shieldinglayer 20 bonded to a first separating layer 30, and a second shieldinglayer 40 bonded to the first separating layer 30 and a second separatinglayer 50. The tape further comprises a third shielding layer 60 bondedto the second separating layer 50 and a third separating layer 61, aswell as a fourth shielding layer 63 bonded to the third separating layer61.

The separator layers are preferably plastic and may comprise anysuitable material, such as polyester, polyethylene terephthalate(“PET”), a polyolefin (such as polypropylene), or combinations thereof,and need not each be formed from the same material(s). The separatorlayers may be any suitable thickness, and need not each be the samethickness. Additionally, while the exemplary shielding tape depicted inFIG. 1 comprises two plastic layers, each disposed between two of thethree respective shielding layers, alternate embodiments of the presentinvention may include any suitable number of plastic layers.

The additional thickness of the shielding tape of the present inventioncan be accommodated by, for example, reducing slightly the diameter ofthe foam dielectric 120 to which it is applied. This allows the diameterof the cable 100 to remain the same as conventional cables, yet theslight reduction in the diameter of the dielectric does notsubstantially degrade the performance of the cable.

Because of the improved inner layer shielding, a bi-shield coaxial cableusing the preferred shielding tape of the present invention (which hasthree shielding layers) can perform as well as some conventionaltri-shield cables without the use of an outer shielding tape. Thislowers the cost and complexity of manufacturing the cable. Additionally,connector attachment is easier since an outer shielding layer wouldnormally need to be removed to install a connector. Likewise, atri-shield coaxial cable using the preferred shielding tape of thepresent invention (which has three shielding layers) can perform as wellas some quad-shield cables without the use of an outer shielding braid.Accordingly, the present invention provides cost savings (e.g., when abi-shield cable of the present invention is used instead of aconventional tri-shield cable) and/or an improvement in shieldingperformance (e.g., when a tri-shield cable of the present invention isused instead of a conventional tri-shield cable).

The shielding tape of the present invention also provides additionalresistance to performance degradation due to wear. Upon repeated flexingof conventional cables, the shielding material (which is preferablyaluminum) in each shielding layer can develop micro-cracks. Thesedegrade shielding performance because the cracks in one shielding layermay align with the cracks in the other shielding layer, and RF can thenegress or ingress through the cracks in each respective layer. Thepresent invention reduces the effects of such cracks because cracks ineach of the three layers are less likely to be aligned to provide a pathfor R.F. egress or ingress as compared to shielding tape with only oneor two shielding layers. This is illustrated in FIG. 4.

The exemplary bi-shield coaxial cable 100 in FIG. 2 comprises a centerconductor 110 preferably formed from copper-clad steel and is about0.0403″ in diameter. The center conductor 110 may be any suitablediameter or thickness, such as between about 0.014″ and about 0.200″ indiameter. The center conductor 110 may also be formed from any othersuitable conductive material, such as copper, copper-plated steel,and/or copper-plated aluminum. The center conductor 110 may be solid ormay comprise multiple conductors, such as stranded wire. Surrounding thecenter conductor 110 is a dielectric 120 that is about 0.18″ in diameterand preferably formed from foam polyethylene. The dielectric may be anysuitable diameter, such as between about 0.040″ and about 0.600″ indiameter. The dielectric 120 may also be solid, and may be formed fromany other suitable material, such as polypropylene or fluorinatedethylene propylene. The shielding tape 10 of the present invention iswrapped around, and preferably bonded (using an adhesive) to thedielectric 120. Surrounding the shielding tape 10 is a braid 130preferably formed from 34-gauge aluminum wire. The braid 130 may beformed from any other suitable material, such as aluminum, copper,copper-plated steel, tinned copper, and/or copper-clad steel. An outerjacket 140 formed from polyvinyl chloride (“PVC”) that is about 0.273″in diameter and about 0.03″ thick surrounds the outer foil. The jacket140 may be any suitable thickness, such as between about 0.007″ and0.080″ thick. The jacket 140 may also be formed from any other flexibleinsulator, such as polyethylene, nylon, and/or TEFLON. The dimensionsrecited above are for an RG-6 type 75-Ohm coaxial cable, but theshielding tape of the present invention may be used with any other formof cable having components of any suitable dimension, such as 50-Ohmcoaxial cables.

Cables employing shielding tape of the present invention may alsoinclude additional layers of shielding tape and/or braid. For example,as shown in FIG. 5A, a tri-shield coaxial cable may include anadditional layer of shielding tape 11 surrounding the braid 130,providing three layers of shielding (the outer foil 11, the braid 130,and the inner foil 10). The outer foil 11 may employ conventionalshielding tape or the shielding tape of the present invention. Inanother example shown in FIG. 5B, the present invention may be used inconjunction with a quad-shield coaxial cable, which includes an outerfoil layer 11 (as described above for the tri-shield cable) and an outerbraid 131 surrounding the outer foil layer 11 to provide four layers ofshielding.

A shielding tape of the present invention may be used in conjunctionwith any other type of shielded cable, such as shielded twisted-pair(“STP”) cabling. In an STP cable, for example, the shielding tape of thepresent invention may be used to surround each pair of one or more pairsof conductors twisted together. As shown in FIG. 6, in some embodimentsthe cable may have a first conductor 110 and a second conductor 111surrounded by a first shielding tape 10. In yet other embodiments, thecable may also have third and fourth conductors, 113 and 115,respectively, surrounded by a second shielding tape 11. A shielding tapeof the present invention may be used to surround any type of conductor,insulator, or other component of a shielded cable and may surround aconductor directly (i.e., there are no intervening structures betweenthe conductor and the tape) or indirectly (i.e., there are one or moreintervening structures between the conductor and the tape, such as adielectric, braiding, or other shielding).

An exemplary process for manufacturing a shielding tape in accordancewith the present invention is depicted in FIG. 3. In this process,lamination is used to bond multiple layers of materials into a sandwichstructure. These materials are processed in the form of wide (typically0.5 to 2 meters) and long (typically 1,000 to 50,000 meters) sheet.After all of the lamination layers are combined, the sheet is slit intomultiple narrow tapes (typically 10 mm to 50 mm wide) and rolled up foruse in manufacturing cable. The shielding tape contains metallic andpolymeric strengthening layers interspersed with adhesive layers. Anoptional hot melt adhesive can be applied to one side of the laminate tobond it to a cable core. The desired tape construction is: A/P/A/P/A/Ewhere A=aluminum, P=polyester and E=EMAA (a hot melt adhesive). Thisprocess can also be used to make other shield tape embodiments whereA=other metal such as copper, lead or Mu metal and P=other polymers suchas polypropylene and E=other adhesives such as EAA.

Referring again to FIG. 3, in step (1), polyester (P) and aluminum (A)sheets are fed from rolls into the laminator. Before lamination thepolyester surface may be activated using a corona treatment whereby thesheet is passed through a high voltage corona discharge etching thesurface to make the adhesive bond more effective. Next a thin layer(about 2 microns) of liquid adhesive is applied to the polyester sheetby spraying or by offset printing. The lamination rolls apply pressureand heat to bond the two sheets together. An oven is used to heat andcure the adhesive. The AP laminate is then rolled up for the nextoperation.

In step (2), the AP sheet and an A sheet are fed from rolls into thelaminator. Once again, corona treatment may be used to activate the Psurface prior to applying a thin layer of liquid adhesive. Afterlamination and oven curing the APA laminate is rolled up for the nextoperation.

In step (3), the sheet of AP manufactured in step 1 is combined with asheet of APA manufactured in step 2 using lamination resulting in anAPAPA layer, which is rolled up. This laminate with 3 metal shieldinglayers can be slit and used as is if no hot melt adhesive layer isneeded.

In step (4), the sheet of APAPA manufactured in step 3 is combined witha sheet of E using the laminator. The E surface may be activated usingcorona treatment to improve adhesive bonding. After lamination and ovencuring the APAPAE laminate is rolled up for slitting.

In step (5), the sheet of APAPA or APAPAE is slit into multiple tapes tothe final width and then rolled up for use in cable manufacture.

As mentioned previously, the laminate shielding tape of the presentinvention provides better shielding effectiveness than cables withconventional tape, even after repeated flexing of the cable. Thiseffectiveness is illustrated in the graph in FIG. 4.

Having thus described preferred embodiments of the invention, othervariations and embodiments that do not depart from the spirit of theinvention will become apparent to those skilled in the art. The scope ofthe present invention is thus not limited to any particular embodiment,but is instead set forth in the appended claims and the legalequivalents thereof. Unless expressly stated in the written descriptionor claims, the steps of any method recited in the claims may beperformed in any order capable of yielding the desired result.

What is claimed is:
 1. A method of manufacturing a coaxial cable, themethod comprising: surrounding a center conductor with a dielectric; andwrapping a shielding tape around the dielectric, wherein the shieldingtape is formed by a method including— subjecting a first surface of afirst plastic sheet to a corona discharge to activate the first surface;applying adhesive to at least one of the activated first surface of thefirst plastic sheet or a first surface of a first metal sheet;laminating the first metal sheet to the first plastic sheet by pressingthe first surface of the first metal sheet against the first surface ofthe first plastic sheet with the adhesive therebetween; subjecting asecond surface of the first plastic sheet to a corona discharge toactivate the second surface; applying adhesive to at least one of theactivated second surface of the first plastic sheet or a first surfaceof a second metal sheet; laminating the second metal sheet to the firstplastic sheet by pressing the first surface of the second metal sheetagainst the second surface of the first plastic sheet with the adhesivetherebetween; subjecting a first surface of a second plastic sheet to acorona discharge to activate the first surface of the second plasticsheet; applying adhesive to at least one of the activated first surfaceof the second plastic sheet or a first surface of a third metal sheet;laminating the third metal sheet to the second plastic sheet by pressingthe first surface of the third metal sheet against the first surface ofthe second plastic sheet with the adhesive therebetween; subjecting asecond surface of the second plastic sheet to a corona discharge toactivate the second surface of the second plastic sheet; applyingadhesive to at least one of the activated second surface of the secondplastic sheet or a second surface of the second metal sheet; andlaminating the second metal sheet to the second plastic sheet bypressing the second surface of the second metal sheet against the secondsurface of the second plastic sheet with the adhesive therebetween,wherein— laminating the first and second metal sheets to the firstplastic sheet forms a first lamination, laminating the third metal sheetto the second plastic sheet forms a second lamination separate from thefirst lamination, and laminating the second metal sheet to the secondplastic sheet forms a third lamination including the first, second, andthird metal sheets individually separated from each other by the firstand second plastic sheets.
 2. The method of claim 1 wherein the methodof forming the shielding tape further includes— heating the firstlamination in an oven to cure at least one of the adhesive between thefirst plastic sheet and the first metal sheet or the adhesive betweenthe first plastic sheet and the second metal sheet; heating the secondlamination in an oven to cure the adhesive between the second plasticsheet and the third metal sheet; and heating the third lamination in anoven to cure the adhesive between the second plastic sheet and thesecond metal sheet.
 3. The method of claim 2 wherein the firstlamination is heated separately from the second lamination.
 4. Themethod of claim 1 wherein subjecting the surfaces of the first andsecond plastic sheets to corona discharges includes etching thesurfaces.
 5. A method of manufacturing a coaxial cable, the methodcomprising: surrounding a center conductor with a dielectric; andwrapping a shielding tape around the dielectric, wherein the shieldingtape is formed by a method including— subjecting a first surface of afirst plastic sheet to a corona discharge to activate the first surface;applying adhesive to at least one of the activated first surface of thefirst plastic sheet or a first surface of a first metal sheet; movingthe first plastic sheet toward a laminating device; moving the firstmetal sheet toward the laminating device, wherein subjecting the firstsurface of the first plastic sheet to a corona discharge includessubjecting the first surface of the first plastic sheet to a coronadischarge before the first sheet reaches the laminating device, andwherein applying adhesive to at least one of the first surface of thefirst plastic sheet or the first surface of the first metal sheetincludes applying adhesive to the first surface of the first plasticsheet after the first plastic sheet has been subjected to the coronadischarge and before the first plastic sheet reaches the laminatingdevice; laminating the first metal sheet to the first plastic sheet bypressing the first surface of the first metal sheet against the firstsurface of the first plastic sheet with the adhesive therebetween,wherein pressing the first surface of the first metal sheet against thefirst surface of the first plastic sheet includes pressing the firstsurface of the first metal sheet against the first surface of the firstplastic sheet at the laminating device; subjecting a second surface ofthe first plastic sheet to a corona discharge to activate the secondsurface; applying adhesive to at least one of the activated secondsurface of the first plastic sheet or a first surface of a second metalsheet; laminating the second metal sheet to the first plastic sheet bypressing the first surface of the second metal sheet against the secondsurface of the first plastic sheet with the adhesive therebetween;subjecting a first surface of a second plastic sheet to a coronadischarge to activate the first surface of the second plastic sheet;applying adhesive to at least one of the activated first surface of thesecond plastic sheet or a first surface of a third metal sheet;laminating the third metal sheet to the second plastic sheet by pressingthe first surface of the third metal sheet against the first surface ofthe second plastic sheet with the adhesive therebetween; subjecting asecond surface of the second plastic sheet to a corona discharge toactivate the second surface of the second plastic sheet; applyingadhesive to at least one of the activated second surface of the secondplastic sheet or a second surface of the second metal sheet; andlaminating the second metal sheet to the second plastic sheet bypressing the second surface of the second metal sheet against the secondsurface of the second plastic sheet with the adhesive therebetween. 6.The method of claim 1 wherein the method of forming the shielding tapefurther includes laminating an adhesive sheet to one of the first orthird metal sheets, and wherein wrapping the shielding tape around thedielectric includes pressing the adhesive sheet against the dielectric.7. The method of claim 1, further comprising: wrapping a braided metalaround the shielding tape; and surrounding the braided metal with anouter jacket.
 8. The method of claim 1 wherein at least one of the firstand second plastic sheets include polyester, and wherein at least one ofthe first, second, and third metal sheets include aluminum.
 9. Themethod of claim 1 wherein at least one of the first and second plasticsheets include polyester, and wherein at least one of the metal sheetsincludes copper and at least one of the remaining metal sheets includesaluminum.
 10. A method of manufacturing a coaxial cable, the methodcomprising: surrounding a center conductor with a dielectric; andwrapping a shielding tape around the dielectric, wherein the shieldingtape is formed by a method including— subjecting a first surface of afirst plastic sheet to a corona discharge to activate the first surface;applying adhesive to at least one of the activated first surface of thefirst plastic sheet or a first surface of a first metal sheet;laminating the first metal sheet to the first plastic sheet by pressingthe first surface of the first metal sheet against the first surface ofthe first plastic sheet with the adhesive therebetween; subjecting asecond surface of the first plastic sheet to a corona discharge toactivate the second surface; applying adhesive to at least one of theactivated second surface of the first plastic sheet or a first surfaceof a second metal sheet; laminating the second metal sheet to the firstplastic sheet by pressing the first surface of the second metal sheetagainst the second surface of the first plastic sheet with the adhesivetherebetween; subjecting a first surface of a second plastic sheet to acorona discharge to activate the first surface of the second plasticsheet; applying adhesive to at least one of the activated first surfaceof the second plastic sheet or a first surface of a third metal sheet;laminating the third metal sheet to the second plastic sheet by pressingthe first surface of the third metal sheet against the first surface ofthe second plastic sheet with the adhesive therebetween; subjecting asecond surface of the second plastic sheet to a corona discharge toactivate the second surface of the second plastic sheet; applyingadhesive to at least one of the activated second surface of the secondplastic sheet or a second surface of the second metal sheet; andlaminating the second metal sheet to the second plastic sheet bypressing the second surface of the second metal sheet against the secondsurface of the second plastic sheet with the adhesive therebetween,wherein— the first metal sheet includes copper, the second and thirdmetal sheets include aluminum, and wrapping the shielding tape aroundthe dielectric includes positioning the first metal sheet between thedielectric and the second and third metal sheets.
 11. A method ofmanufacturing shielding tape, the method comprising: exposing a firstsurface of a first separating layer to a corona discharge; applyingadhesive to at least one of the exposed first surface of the firstseparating layer or a first surface of a first shielding layer; pressingthe first surface of the first shielding layer against the first surfaceof the first separating layer after application of the adhesive;exposing a second surface of the first separating layer to a coronadischarge; applying adhesive to at least one of the exposed secondsurface of the first separating layer or a first surface of a secondshielding layer; pressing the first surface of the second shieldinglayer against the second surface of the first separating layer afterapplication of the adhesive; exposing a first surface of a secondseparating layer to a corona discharge; applying adhesive to at leastone of the first surface of the second separating layer or a firstsurface of a third shielding layer; pressing the first surface of thethird shielding layer against the first surface of the second separatinglayer after application of the adhesive; exposing a second surface ofthe second separating layer to a corona discharge; applying adhesive toat least one of the exposed second surface of the second separatinglayer or a second surface of the second shielding layer; and pressingthe second surface of the second shielding layer against the secondsurface of the second shielding layer after application of the adhesive,wherein, after the pressing steps, the first and second separatinglayers and the first, second, and third shielding layers form alamination in which the first, second and third shielding layers areindividually separated from each other by the first and secondseparating layers.
 12. The method of claim 11, further comprisingheating the lamination to cure at least a portion of the adhesivebetween the first, second, and third shielding layers and the first andsecond separating layers.
 13. The method of claim 12, further comprisingslitting the lamination into multiple tapes.
 14. The method of claim 11wherein— the pressing of the first and second shielding layers againstthe first separating layer forms a first lamination, the pressing of thethird shielding layer against the second separating layer forms a secondlamination separate from the first lamination, and the pressing of thefirst or second shielding layer against the second separating layerforms a third lamination, wherein the third lamination includes thefirst, second and third shielding layers individually separated fromeach other by the first and second separating layers.
 15. The method ofclaim 11 wherein— the first and second separating layers are polymerlayers, and the first, second and third shielding layers are metallayers.
 16. The method of claim 11 wherein— the first and secondseparating layers are polymer layers, at least one of the shieldinglayers is a copper layer, and at least one of the remaining shieldinglayers is an aluminum layer.
 17. The method of claim 5 whereinsubjecting the surfaces of the first and second plastic sheets to coronadischarges includes etching the surfaces.
 18. The method of claim 5wherein the method of forming the shielding tape further includeslaminating an adhesive sheet to one of the first or third metal sheets,and wherein wrapping the shielding tape around the dielectric includespressing the adhesive sheet against the dielectric.
 19. The method ofclaim 5, further comprising: wrapping a braided metal around theshielding tape; and surrounding the braided metal with an outer jacket.20. The method of claim 5 wherein at least one of the first and secondplastic sheets includes polyester, and wherein at least one of thefirst, second, and third metal sheets includes aluminum.
 21. The methodof claim 5 wherein at least one of the first and second plastic sheetsincludes polyester, and wherein at least one of the metal sheetsincludes copper and at least one of the remaining metal sheets includesaluminum.
 22. The method of claim 10 wherein subjecting the surfaces ofthe first and second plastic sheets to corona discharges includesetching the surfaces.
 23. The method of claim 10 wherein the method offorming the shielding tape further includes laminating an adhesive sheetto one of the first or third metal sheets, and wherein wrapping theshielding tape around the dielectric includes pressing the adhesivesheet against the dielectric.
 24. The method of claim 10, furthercomprising: wrapping a braided metal around the shielding tape; andsurrounding the braided metal with an outer jacket.